AbstractAmino‐acids were determined in hydrolysates of two wheat varieties harvested at various stages of maturity, and in flours milled from the wheat samples. During maturation, the concentration in protein of lysine, aspartic acid, glycine. alanine and valine decreased; and concentrations of glutamic acid and proline increased. Milling of wheat into flour reduced the concentrations of lysine, arginine, aspartic acid, threonine, glycine and alanine. Concentrations of glutaniic acid and proline were higher in flour than in wheat proteins. Concentrations of cationic side‐chains in amino‐acids were higher in wheat than in flour, and in both decreased with maturity. Total carboxyl and amide groups were higher in flour than in wheat, and their concentrations increased as the wheat matured. About 84% of the dicarboxylic acids were in amide form. Small changes were observed in concentrations of amino‐acid residues with hydroxylic or hydrophobic groups, and in cystine.